Maria Duenas, 18, was arrested in the fatal stabbing of Adrian Sosa, 17, early Monday morning in the home they both lived in on the Southeast Side. Police were still investigating a motive.

Maria Duenas, 18, was arrested in the fatal stabbing of Adrian Sosa, 17, early Monday morning in the home they both lived in on the Southeast Side. Police were still investigating a motive.

Photo: Bob Owen / San Antonio Express-News

Image 2 of 3

Maria Duenas, 18, was charged with murder in the fatal stabbing Monday of her boyfriend, Adrian Sosa, 17.

Maria Duenas, 18, was charged with murder in the fatal stabbing Monday of her boyfriend, Adrian Sosa, 17.

Photo: Bexar County Sheriff’s Office

Image 3 of 3

Teen arrested in fatal stabbing of another teen

1 / 3

Back to Gallery

SAN ANTONIO – A young woman was arrested in the fatal stabbing of a teenage boy early Monday morning on the city's Southeast Side.

Maria Duenas, 18, confessed to stabbing Adrian Sosa, 17, at a home in the 100 block of Samoth Drive around 5:45 a.m., police said. The suspect and the victim, whose relationship was not immediately known, both lived at the house.

Officers initially thought Sosa might have killed himself, police said, but Duenas later confessed to stabbing him. She told police she and Sosa had earlier argued over something on Facebook, but “the issue was resolved,” a police report says.

Investigators were not sure if the argument led to the stabbing.

Officers were called to the home for a report of a cutting in progress and Duenas initially told them Sosa had come out of the bathroom covered in blood, police said. She yelled, “What did you do?” and tried to put pressure on Sosa's chest to stop the bleeding as another person in the house called 911.